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Kroger at 2,800 locations is our friend with fuel discounts up to 35 gallons. We buy HD, etc 4x points (when available) gift cards. They have hundreds of cards and it's a no brainer if I'm going to shop at those stores anyways. One downside is to use and don't lose those cards. Another downside is few cars take 35 gallons and you lose the balance but our MH sucks up 35 gallons of diesel easily.
Kroger, Cala Foods, City Markets, Copps, Dillons, FoodsCo, Fred Meyer Stores, Fry's, King Soopers, Mariano's Fresh Market, Metro Market, Pick 'n Save, Quality Food Centers (a.k.a. QFC), Ralphs, Food 4 Less, and Smith's Food and Drug. You get the points and some locations may not have a fuel station.
2800 Locations.